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41.
设计并合成了一类新的可用于有机场效应晶体管(OFET)的聚合物半导体材料聚(茚并芴-三苯胺)(pIFTPA1~4), 通过核磁共振谱和凝胶渗透色谱等对聚合物进行了表征, 同时对其场效应薄膜晶体管性能进行了测试. 结果表明, 这些聚合物形成了无定形半导体膜, 在空气中稳定, 其载流子迁移率远高于聚三苯胺(pTPA)类材料, 其中pIFTPA1载流子迁移率高达4×10-2 cm2/(V·s), 开关比为106. 相似文献
42.
新型共轭高分子聚[吡咯2,5-二(3-甲氧基-4-羟基苯甲烯)]的合成与表征 总被引:2,自引:0,他引:2
本文采用两步法合成了一种新型共轭高分子聚 [吡咯 2 ,5 二 (3 甲氧基 4 羟基苯甲烯 ) ],其前聚物聚 [吡咯 2 ,5 二 (3 甲氧基 4 羟基苯甲烷 ) ]可溶于一般的极性有机溶剂 .通过红外、核磁、紫外光谱分析鉴定了产物及其前聚物的结构 .利用DSC与TGA测试分析了所合成聚合物的热学性质 .紫外光谱表明在聚合物链中引入醌式吡咯环结构有利于降低产物的能隙 ,其能隙为 1 14eV ,属窄能隙类共轭聚合物 .经碘掺杂后产物的电导率在半导体的范围内 相似文献
43.
Alexandre Marletta M.L. Vega Y. Galvão Gobato R.M. Faria 《Applied Surface Science》2010,256(10):3018-213
In this work, we have studied the surface morphology of photo-irradiated poly(p-phenylene vinylene) (PPV) thin films by using atomic force microscopy (AFM). We have analyzed the first-order statistical parameters, the height distribution and the distance between selected peaks. The second-order statistical analysis was introduced calculating the auto-covariance function to determine the correlation length between heights. We have observed that the photo-irradiation process produces a surface topology more homogeneous and isotropic such as a normal surface. In addition, the polymer surface irradiation can be used as a new methodology to obtain materials optically modified. 相似文献
44.
《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):401-413
The polymerization of an ionic propargyl derivative, 4-dimethylamino-N-propargylpyridinium bromide (DMAPPB), was carried out by palladium, platinum, and ruthenium chlorides. The polymerization of DMAPPB by these transition metal catalysts proceeded well to give a relatively high polymer yield. The chemical structure of the resulting polymer was characterized by such instrumental methods as elemental analysis, infrared, NMR, UV–visible spectroscopies to have conjugated polymer backbone system bearing 4-dimethylamino-N-methylenepyridinium bromide. The polymer was soluble in DMF, DMSO, and formic acid, and found to be less hygroscopic than those of similar homologues having more smaller substituents. The resulting polymers were mostly black powders and showed the amorphous morphology. 相似文献
45.
Hongliang Guan 《Talanta》2009,79(2):153-1486
In this contribution, we designed a fluorescent thiophene copolymer to detect insertion/deletion mutation in DNA by doping aldehyde group in the main chain. The fluorescence of the copolymer could be dramatically quenched on the addition of single-stranded DNA (ssDNA) via strong electrostatic interactions and electronic/energy transfer. Although the complementary ssDNA made the fluorescence recover, the hydrogen bonds and chemical coupling also played a significant role between the unpaired bases and aldehyde group, which could differentiate the subtle differences in such mutant DNA. The influence of buffer pH, concentration of NaCl, heating time and the temperature was systemically investigated and the proposed method was then successfully applied to detect real sample. With the respect to the linearity, limit of detection precision, specificity, this procedure could provide sensitive methodologies for the rapid detection and identification of nucleic acids. 相似文献
46.
Long Chen František Hartl Howard M. Colquhoun Barnaby W. Greenland 《Tetrahedron letters》2017,58(19):1859-1862
A library of 18 conjugated, rod-like compounds with either one or two viologen residues were synthesized and characterized electrochemically. Containing up to 8 aromatic/heterocyclic rings in conjugation, the members of the library differ in the substitution pattern of electron-withdrawing or -donating groups on the aromatic substituents of the viologen units. The first and second half-wave potentials of each member were found to be linearly correlated with the calculated pKb values of the aromatic end-groups. This relationship will enable the half-wave potentials of related, novel, substituted viologen species to be predicted using a simple, empirical formula. 相似文献
47.
We described the design and synthesis of a colorimetric and ratiometric fluorescent probe based on a conjugated π-electron system that displayed differential fluorescence responses towards cyanide and sulfide and demonstrated its utility in intracellular ion imaging and logic gate. 相似文献
48.
Development of organic semiconductors is one of the most intriguing and productive topics in material science and engineering. Many efforts have been made on the synthesis of aromatic building blocks such as benzene, thiophene and pyrrole due to the facile preparation accompanied by the intrinsic environmental stability and relatively efficient properties of the resulting polymers. In the past, furan has been less explored in this field because of its high oxidation potential. Recently, furan has attracted obsession due to its weaker aromaticity, the greater solubilities of furan-containing π-conjugated polymers relative to other benzenoid systems and the accessibility of furan-based starting materials from renewable resources. This review elaborates the advancements of organic photovoltaic polymers containing furan building blocks. The uniqueness and advantages of furan-containing building blocks in semiconducting materials are also discussed. 相似文献
49.
Junghoon Lee 《Tetrahedron》2010,66(48):9440-9444
Poly(5,5′-(2-hexyldecyl)-bisthiazol-2-yl-amine) (PBTA) is prepared by nickel(0) mediated Yamamoto-type coupling. The photoluminescence (PL) spectrum of PBTA in THF solution displays pure blue emission with a peak centered at 444 nm without any shoulder peaks and the HOMO and LUMO values for PBTA are estimated to be 5.11 and 2.90 eV, respectively. In addition, we have synthesized a novel bisthiazol-2-yl-amine (BTA)-cored donor-acceptor (D-A) chromophore system, namely 5-(4-(diphenylamino)phenyl)-N-(5-(4-(diphenylamino)phenyl)thiazol-2-yl)-N-octylthiazol-2-amine (2-TPA-BTA) in which the electron-donating (D) moiety is triphenylamine group and the electron-withdrawing (A) unit is thiazole group. Furthermore, in this report, we present the complexation studies of both the BTA and 2-TPA-BTA chromophores with Cu(II) and Pd(II), respectively. The crystal structures are established by single-crystal X-ray diffraction analysis. These studies not only provide the general photophysical principles of the materials based on BTA moiety but also encourage progress toward realizing the full potential of its hybrid metal-organic frameworks. 相似文献
50.
Jin Hong Park Dae Hyun Yoon Soo-Hyoung Lee Kyukwan Zong 《European Polymer Journal》2010,46(8):1790-3271
New thieno[3,4-b]thiophene derivatives were prepared via a short and versatile synthetic route. Electrochemical studies of 2-heptenylthieno[3,4-b]thiophene, 2-styrylthieno[3,4-b]thiophene, and 2-phenyl-3-(thieno[3,4-b]thiophene-2-yl)acrylonitrile and the corresponding polymers revealed that raising the HOMO and lowering the LUMO can be attained by functionalizing thieno[3,4-b]thiophene with aromatic resonance-enhancing and electron-withdrawing groups. The bandgap of resulting polymers varied from 0.78 to 1.0 eV, indicating that poly(2-phenyl-3-(thieno[3,4-b]thiophene-2-yl)acrylonitrile) is one of the lowest bandgap polymers ever reported. 相似文献